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Frisoni G.B.,LENITEM Laboratory of Epidemiology | Jack C.R.,Mayo Medical School
Alzheimer's and Dementia | Year: 2011

Hippocampal atrophy is a marker of disease state and progression in Alzheimer's disease. The gold standard to measure hippocampal volume is through manual segmentation. A number of protocols to measure hippocampal volume through manual segmentation have been developed, but the marked heterogeneity of anatomical landmarks has given rise to wide variability of volume estimates. With the aim of fostering the use of hippocampal volume in routine clinical settings, an international task force is currently working on developing a harmonized protocol that will resolve and reduce the present heterogeneity. The task force will then validate the harmonized protocol, develop harmonized probabilistic hippocampal maps, and develop illustrative and educational material on the use of the harmonized protocol and maps. © 2011 The Alzheimer's Association. All rights reserved. Source

Boccardi M.,LENITEM Laboratory of Epidemiology | Ganzola R.,LENITEM Laboratory of Epidemiology | Rossi R.,Psychosocial Rehabilitation Unit | Sabattoli F.,LENITEM Laboratory of Epidemiology | And 8 more authors.
Human Brain Mapping | Year: 2010

Posterior hippocampal volumes correlate negatively with the severity of psychopathy, but local morphological features are unknown. The aim of this study was to investigate hippocampal morphology in habitually violent offenders having psychopathy. Manual tracings of hippocampi from magnetic resonance images of 26 offenders (age: 32.5 ± 8.4), with different degrees of psychopathy (12 high, 14 medium psychopathy based on the Psychopathy Checklist Revised), and 25 healthy controls (age: 34.6 ± 10.8) were used for statistical modelling of local changes with a surface-based radial distance mapping method. Both offenders and controls had similar hippocampal volume and asymmetry ratios. Local analysis showed that the high psychopathy group had a significant depression along the longitudinal hippocampal axis, on both the dorsal and ventral aspects, when compared with the healthy controls and the medium psychopathy group. The opposite comparison revealed abnormal enlargement of the lateral borders in both the right and left hippocampi of both high and medium psychopathy groups versus controls, throughout CA1, CA2-3 and the subicular regions. These enlargement and reduction effects survived statistical correction for multiple comparisons in the main contrast (26 offenders vs. 25 controls) and in most subgroup comparisons. A statistical check excluded a possible confounding effect from amphetamine and polysubstance abuse. These results indicate that habitually violent offenders exhibit a specific abnormal hippocampal morphology, in the absence of total gray matter volume changes, that may relate to different autonomic modulation and abnormal fear-conditioning. © 2009 Wiley-Liss, Inc. Source

Boccardi M.,LENITEM Laboratory of Epidemiology | Frisoni G.B.,LENITEM Laboratory of Epidemiology | Hare R.D.,University of British Columbia | Cavedo E.,LENITEM Laboratory of Epidemiology | And 11 more authors.
Psychiatry Research - Neuroimaging | Year: 2011

Psychopathy is characterized by abnormal emotional processes, but only recent neuroimaging studies have investigated its cerebral correlates. The study aim was to map local differences of cortical and amygdalar morphology. Cortical pattern matching and radial distance mapping techniques were used to analyze the magnetic resonance images of 26 violent male offenders (age: 32 ± 8) with psychopathy diagnosed using the Psychopathy Checklist-Revised (PCL-R) and no schizophrenia spectrum disorders, and in matched controls (age: 35 ± 11). The cortex displayed up to 20% reduction in the orbitofrontal and midline structures (corrected p< 0.001 bilaterally). Up to 30% tissue reduction in the basolateral nucleus, and 10-30% enlargement effects in the central and lateral nuclei indicated abnormal structure of the amygdala (corrected p= 0.05 on the right; and symmetrical pattern on the left). Psychopathy features specific morphology of the main cerebral structures involved in cognitive and emotional processing, consistent with clinical and functional data, and with a hypothesis of an alternative evolutionary brain development. © 2011 Elsevier Ireland Ltd. Source

Boccardi M.,LENITEM Laboratory of Epidemiology | Bocchetta M.,LENITEM Laboratory of Epidemiology | Apostolova L.G.,University of California at Los Angeles | Preboske G.,Mayo Medical School | And 7 more authors.
Journal of Neuroimaging | Year: 2014

Background and purpose: An effort to define and validate a Harmonized Protocol for standard hippocampal segmentation is being carried out. We wished to estimate the effect of magnetic resonance image (MRI) spatial orientation on manual hippocampal segmentations to define optimal standard orientation of MRIs for hippocampal volumetry. Methods: Three expert tracers segmented twice the hippocampi of 10 ADNI subjects on MRI slices oriented perpendicular to the anterior-posterior commissure (AC-PC) line and the long hippocampal axes plane, following internationally harmonized landmarks. We computed intra and interrater reliability figures for total volumes and similarity coefficients. Results: Total volume reliability was similar for both orientations. Similarity coefficients were significantly higher for the AC-PC orientation (exact P = 0.002). Discussion: These data show that AC-PC orientation is slightly more reliable for manual segmentations, possibly due to better visualization of the cerebrospinal fluid spaces separating hippocampal head and amygdala. A Delphi panel of experts has used these data to decide on the optimal orientation for a Harmonized Protocol for hippocampal segmentation. © 2013 by the American Society of Neuroimaging. Source

Minelli A.,University of Brescia | Scassellati C.,Genetic Unit | Cloninger C.R.,University of Washington | Tessari E.,Psychiatric Hospital | And 6 more authors.
Journal of Affective Disorders | Year: 2012

Background: A recent genome-wide association study on Major Depressive Disorder (MDD) identified a specific association with a non-synonymous polymorphism (rs2522833) of a gene encoding the presynaptic protein piccolo (PCLO). A high percentage of patients who develop MDD have particular temperamental traits, such as passivity, pessimism, indecisiveness, and low self-esteem, which are related to the subsequent development of depression. The aims of this study were to perform a replicate case-control study and to conduct the first association study between the rs2522833 polymorphism and depression-related personality traits using the Temperament and Character Inventory (TCI) in a healthy subject sample. Methods: A total of 522 MDD patients and 375 healthy volunteers were enrolled in the study. Two hundred and forty-six controls agreed to fill out the TCI. Results: The results showed that rs2522833 CC homozygotes were more frequent among the depressed patients than in the controls (p < 0.01). The C allele distribution showed a trend in the same direction (p = 0.08). Among controls, we found that the C allele carriers were associated with personality traits increasing vulnerability to depression, including higher Harm Avoidance (HA) and lower in Novelty Seeking (NS). In particular, C allele carriers were more fearful (HA2) and fatigable (HA4), and less impulsive/more deliberate (NS2) and less extravagant/more frugal (NS3). Limitations: The absence of possible epistatic interaction effect. Conclusions: These results provide further support for the involvement of the PCLO gene in MDD and show that this effect may be mediated by influencing personality traits that increase the risk of major depression. © 2012 Elsevier B.V. All rights reserved. Source

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